- Harden coverage generation, by not attempting to compile

runtime/vm/coverage.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/coverage.h"
 
 #include "include/dart_api.h"
 
 #include "vm/compiler.h"
 #include "vm/isolate.h"
 #include "vm/json_stream.h"
 #include "vm/object.h"
 #include "vm/object_store.h"
 
 namespace dart {
 
 DEFINE_FLAG(charp, coverage_dir, NULL,
             "Enable writing coverage data into specified directory.");
 
 
 void CodeCoverage::CompileAndAdd(const Function& function,
                                  const JSONArray& hits_arr) {
   if (!function.HasCode()) {
-    if (Compiler::CompileFunction(function) != Error::null()) {
+    // If the function should not be compiled or if the compilation failed,
+    // then just skip this method.
+    // TODO(iposva): Maybe we should skip synthesized methods in general too.
+    if (function.is_abstract() || function.IsRedirectingFactory()) {
+      return;
+    }
+    if (function.IsNonImplicitClosureFunction() &&
+        (function.context_scope() == ContextScope::null())) {
+      // TODO(iposva): This can arise if we attempt to compile an inner function
+      // before we have compiled its enclosing function or if the enclosing
+      // function failed to compile.
+      OS::Print("### Coverage skipped compiling: %s\n", function.ToCString());
+      return;
+    }
+    const Error& err = Error::Handle(Compiler::CompileFunction(function));
+    if (!err.IsNull()) {
+      OS::Print("### Coverage failed compiling:\n%s\n", err.ToErrorCString());
       return;
     }
   }
   ASSERT(function.HasCode());
 
   Isolate* isolate = Isolate::Current();
   // Print the hit counts for all IC datas.
   const Script& script = Script::Handle(function.script());
   const Code& code = Code::Handle(function.unoptimized_code());
   const Array& ic_array = Array::Handle(code.ExtractTypeFeedbackArray());
@@ skipping 129 matching lines @@
   void* file = (*file_open)(filename, true);
   if (file == NULL) {
     OS::Print("Failed to write coverage file: %s\n", filename);
     return;
   }
   (*file_write)(stream.buffer()->buf(), stream.buffer()->length(), file);
   (*file_close)(file);
 }
 
 }  // namespace dart